A Cochrane review included 6 studies with a total of 390 subjects. Meta-analysis of these trials showed a statistically significant effect of potassium nitrate toothpaste on air blast and tactile sensitivity at the 6 to 8 weeks follow up (air blast sensitivity score: standardized mean difference –1.25, 95% CI –1.65 to –0.851 in favour of treatment). The subjective assessment failed to show a significant effect at the 6 to 8 week assessment.
Comment: The quality of evidence was downgraded by sparse data and inconsistency.